Beside the temperature, the humidity, i. the water vapor content of the air. The humidity is a meteorologically important parameter. This becomes understandable when one considers that in a large number of meteorological phenomena, water participates in its various forms. This applies not only to the clouds, the fog and the many types of precipitation, in the formation of which as well as in the evaporation of huge amounts of energy are implemented, but also for the emission and absorption of long-wave radiation, for which the water vapor content of the air is essential.
